Stress analysis of stiffened cylindrical shells under a static load

Abstract

The presented work contains the numerical strain analysis of a ribbed shell of a rotary drum with two riding rings rigidly fixed to the drum shell. In the first stage of the conducted research a numerical model of a cylindrical shell was built with two stiffening rings of dimensions corresponding to the common constructions used in chemistry or the cement industry. The boundary conditions were set according to the mentioned machines working conditions and the model was subjected to loads corresponding to real data. The correctness of the numerical model was verified by a comparison with the results obtained in analytical calculations. The Fursow method was used in the analytical method. In the next step the model had been extended to include the longitudinal ribs added within the drum around the perimeter of the cylindrical shell. The ribs work as lifting flights. The bulk material was lifted by the flights during the rotation of the drum allowing for convective heat exchange between the material intended for drying and the air inside the shell. The bulk material was treated as a rigid body and the cylindrical shell of the drum was analyzed under its dead load. The effect of temperature was omitted due to the fact, that the drying was carried out at the temperature not exceeding 80 °C, hence the variability of Young’s modulus was negligible. An analysis was performed with the use of numerical methods and commercial software ANSYS. The influence of the position of material loads on the stress and deformation reduction of the cylindrical shell and running ring was analyzed. As a result of the numerical simulations, the distribution of bending moments and the areas of greatest stress concentration and maximum strain were identified.